SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 2) ExpressionList (children 1) Function minMerge (children 1) ExpressionList (children 1) Identifier x TablesInSelectQuery (children 1) TablesInSelectQueryElement (children 1) TableExpression (children 1) Subquery (children 1) SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 2) ExpressionList (children 1) Function plus (alias x) (children 1) ExpressionList (children 2) Function minState (children 1) ExpressionList (children 1) Identifier a Function minState (children 1) ExpressionList (children 1) Identifier b TablesInSelectQuery (children 1) TablesInSelectQueryElement (children 1) TableExpression (children 1) TableIdentifier add_aggregate